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Diffstat (limited to 'common/util.c')
| -rw-r--r-- | common/util.c | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/common/util.c b/common/util.c deleted file mode 100644 index 7e0d54299..000000000 --- a/common/util.c +++ /dev/null | |||
| @@ -1,101 +0,0 @@ | |||
| 1 | /* | ||
| 2 | Copyright 2011 Jun Wako <wakojun@gmail.com> | ||
| 3 | |||
| 4 | This program is free software: you can redistribute it and/or modify | ||
| 5 | it under the terms of the GNU General Public License as published by | ||
| 6 | the Free Software Foundation, either version 2 of the License, or | ||
| 7 | (at your option) any later version. | ||
| 8 | |||
| 9 | This program is distributed in the hope that it will be useful, | ||
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
| 12 | GNU General Public License for more details. | ||
| 13 | |||
| 14 | You should have received a copy of the GNU General Public License | ||
| 15 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
| 16 | */ | ||
| 17 | |||
| 18 | #include "util.h" | ||
| 19 | |||
| 20 | // bit population - return number of on-bit | ||
| 21 | uint8_t bitpop(uint8_t bits) | ||
| 22 | { | ||
| 23 | uint8_t c; | ||
| 24 | for (c = 0; bits; c++) | ||
| 25 | bits &= bits - 1; | ||
| 26 | return c; | ||
| 27 | /* | ||
| 28 | const uint8_t bit_count[] = { 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 }; | ||
| 29 | return bit_count[bits>>4] + bit_count[bits&0x0F] | ||
| 30 | */ | ||
| 31 | } | ||
| 32 | |||
| 33 | uint8_t bitpop16(uint16_t bits) | ||
| 34 | { | ||
| 35 | uint8_t c; | ||
| 36 | for (c = 0; bits; c++) | ||
| 37 | bits &= bits - 1; | ||
| 38 | return c; | ||
| 39 | } | ||
| 40 | |||
| 41 | uint8_t bitpop32(uint32_t bits) | ||
| 42 | { | ||
| 43 | uint8_t c; | ||
| 44 | for (c = 0; bits; c++) | ||
| 45 | bits &= bits - 1; | ||
| 46 | return c; | ||
| 47 | } | ||
| 48 | |||
| 49 | // most significant on-bit - return highest location of on-bit | ||
| 50 | // NOTE: return 0 when bit0 is on or all bits are off | ||
| 51 | uint8_t biton(uint8_t bits) | ||
| 52 | { | ||
| 53 | uint8_t n = 0; | ||
| 54 | if (bits >> 4) { bits >>= 4; n += 4;} | ||
| 55 | if (bits >> 2) { bits >>= 2; n += 2;} | ||
| 56 | if (bits >> 1) { bits >>= 1; n += 1;} | ||
| 57 | return n; | ||
| 58 | } | ||
| 59 | |||
| 60 | uint8_t biton16(uint16_t bits) | ||
| 61 | { | ||
| 62 | uint8_t n = 0; | ||
| 63 | if (bits >> 8) { bits >>= 8; n += 8;} | ||
| 64 | if (bits >> 4) { bits >>= 4; n += 4;} | ||
| 65 | if (bits >> 2) { bits >>= 2; n += 2;} | ||
| 66 | if (bits >> 1) { bits >>= 1; n += 1;} | ||
| 67 | return n; | ||
| 68 | } | ||
| 69 | |||
| 70 | uint8_t biton32(uint32_t bits) | ||
| 71 | { | ||
| 72 | uint8_t n = 0; | ||
| 73 | if (bits >>16) { bits >>=16; n +=16;} | ||
| 74 | if (bits >> 8) { bits >>= 8; n += 8;} | ||
| 75 | if (bits >> 4) { bits >>= 4; n += 4;} | ||
| 76 | if (bits >> 2) { bits >>= 2; n += 2;} | ||
| 77 | if (bits >> 1) { bits >>= 1; n += 1;} | ||
| 78 | return n; | ||
| 79 | } | ||
| 80 | |||
| 81 | |||
| 82 | |||
| 83 | uint8_t bitrev(uint8_t bits) | ||
| 84 | { | ||
| 85 | bits = (bits & 0x0f)<<4 | (bits & 0xf0)>>4; | ||
| 86 | bits = (bits & 0b00110011)<<2 | (bits & 0b11001100)>>2; | ||
| 87 | bits = (bits & 0b01010101)<<1 | (bits & 0b10101010)>>1; | ||
| 88 | return bits; | ||
| 89 | } | ||
| 90 | |||
| 91 | uint16_t bitrev16(uint16_t bits) | ||
| 92 | { | ||
| 93 | bits = bitrev(bits & 0x00ff)<<8 | bitrev((bits & 0xff00)>>8); | ||
| 94 | return bits; | ||
| 95 | } | ||
| 96 | |||
| 97 | uint32_t bitrev32(uint32_t bits) | ||
| 98 | { | ||
| 99 | bits = (uint32_t)bitrev16(bits & 0x0000ffff)<<16 | bitrev16((bits & 0xffff0000)>>16); | ||
| 100 | return bits; | ||
| 101 | } | ||
